Paraneoplastic coma and acquired central alveolar hypoventilation as a manifestation of brainstem encephalitis in a patient with ANNA-1 antibody and small-cell lung cancer

Introduction: Paraneoplastic neurological disorders are a well recognized complication of malignancy. Methods: A case report to expand the currently described clinical manifestations of type 1 antineuronal antibody (ANNA-1)-associated paraneoplastic encephalomyelitis to include coma. Results: We present an unusual case of fluctuating coma and rapid fulminant progression to acute respiratory failure from central alveolar hypoventilation caused by ANNA-1 paraneoplastic encephalomyelitis associated with small-cell lung carcinoma. Paraneoplastic infiltration of the brainstem and cerebellum, including respiratory and arousal centers, was documented on autopsy. Conclusions: Paraneoplastic encephalomyelitis should be considered as a possible cause of coma and central alveolar hypoventilation.